In oil and gas wells, a gravel packing assembly pumps gravel slurry down tubing and exits the tubing to allow the slurry to flow into an annulus formed between a screen and the well casing or open hole. The liquid in the slurry flows into the formation of the well and/or the openings in the screen, which are sized to prevent the gravel from entering the screen. The gravel collects around the screen to form the gravel pack. The gravel allows flow of produced fluids therethrough and into the screen while blocking the flow of particulates produced with the formation fluids.
When bridges caused by obstructions are created in the annulus, secondary flow path tubes, which are in fluid communication with the gravel slurry, allow the slurry to flow through the tubes and out into the annulus through emitters downstream of the bridge. Thus, the annulus below the bridge can be packed with the gravel. Where no annular obstruction exists, the secondary flow path tube is naturally bypassed for the easier flowing annulus.
When the secondary flow path tubes do become a slurry conduit, because of the high pressure in the secondary flow path tubes, the slurry tends to exit at a high velocity. Slurry being by nature erosive, a property exacerbated by high velocity, can detrimentally affect the secondary flow path tubes. The art has clamped the secondary flow paths to the outside of the sand screen and then has run an additional shroud over the paths. While the additional shroud helps protect the secondary flow paths during operation, the assembly process is complicated.